I made a sled out of a plastic snow sled I bought at walmart for less than 10 dollars tied a rope to it. Then you can get some sand bags from home depot and put it right on the sled. I used a decent nylon rope for a belt and a tow line…
That’s if your not too embarrased to use it…
I used to doubt the hills until this year when I really started to focus on proper technique… I wound up smashing my 30m PRs after the GPP… I’d do the hills if you have them near you.